Function makeDragBox

src/plots/cartesian/dragbox.js:50–1039

(gd, plotinfo, x, y, w, h, ns, ew)

//          'ns' - top and bottom together, difference unchanged
//      ew - same for horizontal axis
function makeDragBox(gd, plotinfo, x, y, w, h, ns, ew) {
    // mouseDown stores ms of first mousedown event in the last
    // `gd._context.doubleClickDelay` ms on the drag bars
    // numClicks stores how many mousedowns have been seen
    // within `gd._context.doubleClickDelay` so we can check for click or doubleclick events
    // dragged stores whether a drag has occurred, so we don't have to
    // redraw unnecessarily, ie if no move bigger than MINDRAG or MINZOOM px
    var zoomlayer = gd._fullLayout._zoomlayer;
    var isMainDrag = (ns + ew === 'nsew');
    var singleEnd = (ns + ew).length === 1;

    // main subplot x and y (i.e. found in plotinfo - the main ones)
    var xa0, ya0;
    // {ax._id: ax} hash objects
    var xaHash, yaHash;
    // xaHash/yaHash values (arrays)
    var xaxes, yaxes;
    // main axis offsets
    var xs, ys;
    // main axis lengths
    var pw, ph;
    // contains keys 'xaHash', 'yaHash', 'xaxes', and 'yaxes'
    // which are the x/y {ax._id: ax} hash objects and their values
    // for linked axis relative to this subplot
    var links;
    // similar to `links` but for matching axes
    var matches;
    // set to ew/ns val when active, set to '' when inactive
    var xActive, yActive;
    // are all axes in this subplot are fixed?
    var allFixedRanges;
    // do we need to edit x/y ranges?
    var editX, editY;
    // graph-wide optimization flags
    var hasScatterGl, hasSplom, hasSVG;
    // collected changes to be made to the plot by relayout at the end
    var updates;
    // scaling factors from css transform
    var scaleX;
    var scaleY;

    // offset the x location of the box if needed
    x += plotinfo.yaxis._shift;

    function recomputeAxisLists() {
        xa0 = plotinfo.xaxis;
        ya0 = plotinfo.yaxis;
        pw = xa0._length;
        ph = ya0._length;
        xs = xa0._offset;
        ys = ya0._offset;

        xaHash = {};
        xaHash[xa0._id] = xa0;
        yaHash = {};
        yaHash[ya0._id] = ya0;

        // if we're dragging two axes at once, also drag overlays